SOLUTION: How do you work this problem out? 1. P∙P 2. Q→~P ∴ ~Q

Question 459028: How do you work this problem out?
1. P∙P
2. Q→~P ∴ ~Q
Answer by jim_thompson5910(35256) (Show Source): You can put this solution on YOUR website!

1.   P * P
2.   Q -> ~P    / :. ~Q
--------------------------
3.   P                   1      Simplification
4.   ~~P                 3      Double Negation
5.   ~Q                  2,4    Modus Tollens

RELATED QUESTIONS
Solve use reductio ad absurdum 1. ~P→(R∙S) 2.... (answered by math_helper)

write a direct proof using the eight rules of inference (C → Q) � (~L →... (answered by Edwin McCravy)

1. (Q∨R)→(W∨U) 2. W→P 3. (answered by jim_thompson5910)

1. ~P∨Q 2. Q→R ∴ P→R 1. R∨~Q 2. P→Q 3. ~R (answered by Edwin McCravy)

Prove this 1. P∨Q 2. (Q∙~R)→S 3.... (answered by jim_thompson5910)

1. ~M 2. (~M∙~N)>(Q>P) 3. ~N 4. P>R (answered by jim_thompson5910)

Complete the following proofs using the Conditional Proof method. 1) 1. ~(P ∙... (answered by solver91311)

1. (Q∨R)→(W∨U) 2. W→P 3. Q∙T 4. U→Z 5. S→M (answered by jim_thompson5910)

P∙ Q R⊃ ~Q / ~R∨ ~P (answered by jim_thompson5910)

SOLUTION: How do you work this problem out? 1. P&#8729;P 2. Q&#8594;~P &#8756; ~Q

SOLUTION: How do you work this problem out? 1. P∙P 2. Q→~P ∴ ~Q